Recent developments by our team of engineers and technicians have improved the efficiency and cost of the chemical additive, resulting in final mix that in the laboratory appears to perform better than that of conventional HMA with a cost possibly equal to or even less than that of conventional HMA. A "green" product to replace the conventional product without increasing the cost.
However, before widespread implementation of this technology can occur, engineers must be satisfied that the resulting mixtures will be at least as strong and durable as what is currently being provided. Technicians and construction personnel must acquaint themselves with the characteristics and behavior of these new materials. This research is needed to measure the degree of environmental improvement, fundamental mix characteristics, and the impact on performance from this new technology.
The road industry has been seeking for many years ways to reduce the amount of energy
required to manufacture hot mix asphalt (HMA) in order to combine energy savings and
environmental benefits. It is logical that one approach to achieving these goals would involve
methods to reduce material production temperatures. The concept of warm-mix asphalt has
been introduced as a means to these ends. Low emission asphalt (LEA) is one such
technology. However, before widespread implementation of this technology can occur,
engineers must be satisfied that the resulting mixtures will be at least as strong and durable
as conventional HMA. Technicians and construction personnel must acquaint themselves with
the characteristics and behavior of these new materials. This report measures the degree of
environmental improvement, fundamental mix characteristics, and the impact on
performance from this new technology.
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The currently proposed solutions to improve the energy efficiency of asphalt mixing
processes are categorized into warm and half warm, depending on whether their
manufacturing temperature is above or below 100C. Evaluating the energy content of such
asphalt mixes is essential for its environmental validation. This paper uses thermodynamic
methods to determine the energy content of six types of manufacturing representative of
hot, warm, and half warm mixes. This paper was presented at TRB in 2008.
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